Traverse mechanism for card stripping apparatus



. TRAVERSE MECHANISM FOR Dec. 19, 1944. wm 2,365,654

CARD APPARATUS Filed Sepjt. 10,

on the screw along its the disengagement of the parts at the end of thePatented Dec. 19, 1944 TRAVERSE MECH'ANISM FOR CABD STRIPPING APPARAT USCharles E. White, Abington,

Abington Textile Machinery Mass., a trust of Massachusetts Mass.,assignor to Works, Boston,

Application September 1-0, 1943, Serial No. 501,758 6 Ciainis. (CL19-109) The present invention is concerned with improvements in thetraverse mechanism of card stripping apparatus. li 1 In pneumatic cardstripping apparatus of the general type shown in the United Statespatent to Clark, No. 1,614,103,- the suction nozzles are mounted on anozz1e' carriagewhich is given a traversing movement by a rotating leadscrew, the carriage during stripping being connected with the traversescrew by a pawl or dog, the nose of which runs in the thread of thescrew. Because of the proximity of fly during the operation of themachine, it is not possible to use oil to lubricate the parts. Thefriction is therefore considerable and the wear of the parts relativelyrapid.

Furthermore,at the end of each traverse, it is necessaryrto disengagethe pawl from the screw, which is done automatically by an abutment intowhich the pawl runs to knock-out the latter from the screw. Thisforcible disengagement tends in time to chip the screw m the zone wheredisengagement takes place; so that y frequently, in making repairs, itisnecessaryto replace the entire screw along with the pawl.

I t is the object of the present invention to improve the drivingconnections between the traverse screw and nozzle carriage of pneumaticcard stripping apparatus by providing rolling engagement in place ofsliding contact between the parts. More specifically, the inventioncontemplates the provision of a roller pawl of novel design, which notonly substantially reduces wear length, but also permits traverse totake place smoothly and without damage to thepthreads of the screw.

i These objects have been attained by providing in accordance with theinvention a pawl inthe form of a roller, the periphery of which runs inthe thread of the traverse screw. The roller is of cup-shaped contour topermit engagement with the screw at a substantial of roller axis to theaxis of the screw, in order that the iorces to which the bearing of theroller is subjected may be largely radial. This angular relationship ofroller and screw axes is actually a compound V angle, based as willhereafter appear on; flare angles of the roller and on angles ofinclination and tilt of the roller axis so that after the roller hasbeen placed in engagement with the screw at the beginning of a traverse,the parts are automatically maintained in freely rolling engagementwithout the use of looking devices or other retaining means. At the endof the traverse, the

pawl may readily be rolled out of engagement without injury to thescrew;

In the drawing illustrating the invention, Fig. 1 is a view of a portionof the traverse screw of Vacuum card strpping mechanism of the samegeneral type as shown in the Clark patent above referred too, with aportion of the nozzle carriage shown in section and illustrating theroller pawl in operative engagement with the thread of the screw; Fig. 2is a sectional view of the parts shown in Fig. 1, taken on the line ofsaid figure; and Fig. 3 is a sectional view, taken on the line 33 ofFig. l.

Thetraverse screw, indicated at 8, is of conventional design for Vacuumstripping mechanisms. A pitch angle of 915 is indicated, although theroller pawl to be described may be employed with traverse screws havinga greater or lesser pitch angle as desired or required. The traversescrew runs within a traverse tube H! fixed in the machine frame; thetube providing a support for the nozzle carriage, a portion of whichis.indicated at I2. The sleeve is slotted along its length to provideaccess for the pawl.

The roller pawl l4 is of cup-shaped contour, and is so mounted that thethread of the screw is -engaged bythe outer edge |6 of the flaring rim.The roller is pivotally mounted on a pawl lever l8 by means of ashouldered rivet 20. The pawl lever is pivotally connected to the nozzlecarriage 12 by a pin 22 to enable the roller pawl to be moved into andout of engagement with the traverse screw.

In describing the various angular relationships of the parts by whichthe objects of the invention are achieved, it is convenient to definethe several angles which are involved. The first of these angles is theflare of the roller, being the angle between the outer wall of theroller and the center line or axis; Let such angle be termed A, asindicated on the drawing. A suitable value for this angle has been foundto be in the .dicated in Fig. 1 as angle B, is chosen in relation to theangle of flare of the roller so that the sum of the two angles issomewhat greater than 90-. Thus, with an angle of approximately betweenaxes of screw and roller, as indicated, a 15 difference results. Thisangle, represented by C in Fig. 1, insures that the engagement betweenscrew and roller will take place between the rounded outer rim portionof the roller and the base of the screw thread.

pivotally mounted on the Due to the relatively large (60) angle betweenaxes of screw and roller, a substantial proportion of the forcestransmitted by the screw to the roller in driving the nozzle carriage isdirected radially of the roller with a relatively small component offorce in an axial direction at one point of the rim. Since this lattercomponent tends to{skew the roller on its: pivot, it is desirable thatthis component be as small as practical in view of the rapid wear whichresults with bearings of limited length To insure, once the roller pawlhas been placed in engagement with the screw, that the parts willautomatically remain in driving engagement throughout the traversewithout the use of locking devices, the roller is tilted at an anglewhich is hereinafter referred to as a run-in angle. This angle,indicated at D in Fig. 3, is the angle between the plane of rotation ofthe roller pawl and a tangent to the screw at the point of contactbetween the screw and roller. This angle need not be more than a fewdegrees,. an angle of approximately 5 having been found satisfactory.The tilt of the roller must be: in a direction toward that portion ofthe screw rotating toward the roller, to drive the nozzle carriage inthe direction indicated by arrow 24.

While this run-in angle insures that the roller will automaticallyremain in engagement With the screw once the traverse has been started,no

difficulties are involved in disengaging the parts at the end of thestroke. As the limit of the traverse is approached, the handle 26 of thepawl lever engagesz the sloping face 28 of an abutment carried by themachine frame. Further advance of the carriage results in swinging thelever in a direction to disengage the roller, the latter being lrolled-out of the screw smoothly and without subjecting the screw toincreased wear in this zone.

While certain angles have been indicated for the flare of the rollerpawl and the inclination of the axes of traverse screw and roller, theseparticular angles are not in themselves extremely critical. It is,however, important that the sum of the fiare angle and the inclinationangle be somewhat greater than 90, in order that the en gagement betweenscrew and roller be With the outer rim of the roller. By making theangle between axes of roller and screw of the order of 60, adequateclearance may be provided 1'0r the roller, yet the forces at its bearingare predominantly radial, so that undue wear on the bearing is avoidedThese interrelated angles, together with the runin angle, engage thescrew in rolling result that operation for long made possible withoutrepair contact, with the periods of time is or replacement of the parts.

Iclaim as my invention:

1. A driving connection for the traverse motion of card strippingappa.ratus comprising, in combination with the nozzle carriage, a rollerpawl carriage for rolling engagement with the traverse scre said pawlbeing cup-shaped to provide a fiaring rim portion, the axis of the pawlbeing inclined to the axis of the screw to provide engagement betweenthe thread of the screw and the Outer rim portion of the pawl, said axisof the pawl also being tilted in non-intersecting relation to the axisof the screw enable the pawl to to provide run-in between the pawl andthe screw.

2. A driving connection for the traverse motion of card strippingapparatus comprising, in combination with the nozzle carriage, a rollerpawl pivotally mounted on the carriage for rolling engagement with thetraverse screw, said pawl being cup-shapd to provide a flaring rimportion, the axis of the roller pawl being inclined to the axis of thescrew and the plane of rotation of the roller pawl being inclinedrelativeto a tangent to the screw at the point of contact of screw andpawl.

3. A driving connection for the traverse motion of card strippingapparatus comprising, in combination With the nozzle carriage, a. rollerpawl pivotally mounted on the carriage for rolling engagement with. thetraverse screw, said pawl being cup-shaped to provide a rim portionfiaring outwardly from the axis at an angle of approximately 40, and.the axis of the roller pawl being inclined to the axis of the screw atan angle of approximately 60.

4. A driving connection for the traverse motion of card strippingapparatus comprising, in com bination With the nozzle carriage, a rollerpawl pivotally mounted on the carriage: for rolling engagement with thetraverse screw, said pawl being cup-shaped and having a ,rim portionflaring outwardly from the axis of the roller at an angle thereto,andthe axis of the roller being disposed at an angle to the axis of thescrew, the sum of said angles being greater than to enable the outerportion of the rim of the pawl to engage the thread of the screw.

5. A driving connection for the traverse motion of card strippingapparatus comprising, in com-' and roller, said angle of tilt being ofthe order of 5 and in a direction toward that portion of the screwrotating toward the roller to provide relative run-in between thematically maintain. the roller pawl in engagement with the screw.

6. Traverse mechanism for pneumatic stripping apparatus of cards,comprising in combina-tion, a traverse screw, a nozzle carriage, a pawllever, and a, roller pawl carried by said lever, the pawl consisting ofa. cup-shaped member pivotally mounted on said lever and positioned toengage the screw with the axis of the pawl inclined at an angle ofapproximately 60 to the axis of the screw, said roller having anoutwardly fiaring rim portion inclined at an angle of approximately 40to the axis of the roller, the plane of rotation of the roller beingtilted at an angle of approximately 5 with respect to a tangent to thescrew at the point of contact between roller and screw, the tilt beingtowards the screw relative tothat portion thereof rotating towards theroller.

' CHARLES E. WHITE.

parts and thereby auto-

